Step 2 is open label. Regimens include 2 or 3 nucleoside reverse transcriptase inhibitors (NRTIs) in combination with EFV, atazanavir (ATZ), ritonavir-boosted ATZ, or tenofovir disoproxil fumarate (TDF). Patients on Arm B treatment who have an HIV RNA level less than 200 copies/ml within the past 8 weeks are eligible for randomization to open-label intensification of Arm B on Step 3.